Science, 9 November 2007

Correlation of the Highest-energy Cosmic Rays with Nearby Extragalactic Objects

On the Cover: All-sky projection of highest-energy cosmic rays detected by the Pierre Auger Observatory (open circles) that are correlated with the positions of nearby quasars (crosses), a measure of the local galaxy distribution. The supergalactic and Milky Way planes are marked. The background shows a composite image of a nearby galaxy (M82) observed by NASA’s Spitzer, Hubble, and Chandra space observatories.